Here at BookGorilla, we take the responsibility to provide curated recommendations a bit more seriously. By comparison, over 85% of the titles that we recommend at BookGorilla are provided based solely on the merit of the book and the deal, without any associated advertising revenue.

We think the difference shows up when one compares the books recommended on each site. We’re here to save our readers time and money by providing the books you have always wanted to read at prices you never dreamed possible.

It’s not so much that “we try harder,” as that we are trying for different things. We’re aiming for your bedside reading table, not your remainder table. And we’ve got our eyes on the prize of providing value for readers, not for venture capital investors.

For many readers who have been keeping up with those daily side-by-side comparisons that have shown BookGorilla to be far outpacing BookBub when it comes to recommending great book deals on bestselling books by well-known authors, there has been a pretty obvious question:

“Why doesn’t BookBub just work harder to find the kind of books that are featured by BookGorilla each day?”

The answer? It’s complicated, but it’s all about the bottom line. BookBub has nearly 10 million reasons to focus on books that it needs readers to buy, while BookGorilla’s more customer-centric mission is aimed at providing readers with books they already wanted at prices they never dreamed were possible.

We’re sure that BookBub would like to be able to present great deals on more prominent books, but they are constrained by a few obvious structural facts that are implicit in their business model:

For starters, BookBub depends on two major revenue streams, which together provide revenues of over $26,000 daily, or about $9.7 annually, according to our estimates based on information provided on the company’s website. For instance, the 27 books recommended on BookBub’s deals page yesterday would have paid BookBub just over $16,000 for their placement on BookBub’s “curated” list, and are likely to have brought the company an additional $10,000, at least, in affiliate fees such as Amazon Associates proceeds. “Curated” is as “curated” does, but that $16,000 daily would be a lot of money to leave on the table if BookBub were to make a strategic decision to add value for readers by opting to drop some of those 27 ad-supported spots in favor of more prominent, highly desired books at great deal prices such as those featured on the BookGorilla site.

Screenshot of third-party banner ad in March 15, 2014 BookBub alert.

But with that much money coming in, one might ask, wouldn’t BookBub still be profitable if it decided to improve the quality of its daily recommendations by doing just that: replacing some ad-supported spots with more widely known books by bestselling authors? Sure, but then BookBub would run into another difficult structural challenge: the company is increasingly in the position of having to answer to venture capitalists and other angel funders. Indeed, since its May 2014 announcement that it had raised $3.8 million in Series A funding, BookBub has ratcheted up its ad-supported offerings: from 15 to 20 daily spots in early 2014 to 25 to 30 now, with no concomitant increase in bestsellers or other well-known titles. Meanwhile, Bookbub has recently been experimenting with adding paid third-party advertising banners served by LiveIntent (see screenshot above at right ) to the millions of emails it sends out to self-identified book lovers each day. Naturally, the point at which a company accepts investor funding is usually the point at which its autonomy with respect to its mission begins to come under pressure.

While BookBub founder Josh Schanker keeps the lowest of online profiles, it would not be surprising to see him exit with a payday in the high nine figures or beyond, given his history as a serial entrepreneur and BookBub’s impressive success to date. With such heady outcomes looming for Schanker and other key players, one can’t really expect BookBub to allow short-term revenues to soften in favor of a longer-term commitment to adding value for readers by changing the ratio between ad-supported spots and truly curated recommendations of the best books available at the best prices each day.

Not to worry. BookBub is doing just fine. But with its need to get readers to buy the books that it wants them to buy even if they’ve never heard of the title or the author before, it does present a real contrast in mission with our BookGorilla upstart.

Chances are, if you’re reading this, you already know what that contrast in mission is all about. Although BookGorilla certainly continues to sell all the ad-supported spots it makes available, it remains true that fewer than 20% of all the books recommended by BookGorilla are ad-supported. That leaves us free to pick the best deals at the best prices each day, and to remain true to our mission, which is to provide readers with books they had already wanted to read at prices they never dreamed possible.

Earlier this week we shared a picture that may have surprised some of our readers: a side-by-side comparison of Wednesday’s top ebook recommendations from our BookGorilla service and another popular service called BookBub. If you were looking for great deals on titles that most readers have heard of (which is certainly not the only worthwhile measuring stick), it was clear that you’d be far more likely to find them on BookGorilla than on BookBub.

If we say so ourselves. And we do.

Of course there are plenty of good reasons why avid readers may want to subscribe to both services — after all, both are totally free. And there are other ways in which BookBub has a clear edge, including:

If price-per-unit is your main consideration in acquiring books for your Kindle library, you may well want to go with BookBub. In today’s comparison, for example, BookBub’s top book recommendations were available for an average price of $1.45 in the Kindle store, while the average price for BookGorilla’s top recommendations was $1.91.

If you participate in a Kindle author fantasy league and you want to know which previously unknown book is most likely to vault from a sales ranking of 688,529 to the Top 100 Kindle bestsellers in the next 24 hours, BookBub’s also your best bet. It’s true that several books featured on BookGorilla make Amazon’s Movers and Shakers list each day, but they generally don’t have as far to go to make that list. And subject to check, BookBub has approximately a gazillion subscribers, many of whom still open each day’s BookBub alert. Numbers like that are sure to move just about any needle, no?

Finally, among authors and publishers for whom money is no object when it comes to their marketing budgets, BookBub’s a clear choice. You may spend as much as $1,975 for a single promotion on BookBub, but you’re likely to get a bigger bump than you will get for $40 to $200 with BookGorilla or similar amounts with other well-managed services such as eReader News Today.

We could probably go on, but of course we’re not here to do BookBub’s work; they are very effective on their own behalf.

And as we will try to explain in a new post this weekend, there are about 9.5 million great reasons why BookBub wants readers to focus on the books that it includes in its daily ebook alert, even if you’ve never heard of them before.